A New Method for Radar Altimeter Sea State Bias Estimation Based on Crossover Data and Three-dimensional Nonparametric Model

The Sea State Bias (SSB) is an important source of error in satellite altimetry. Operational SSB correction models are based on the altimeter-measured wind speed (U) and Significant Wave Height (SWH). This paper presents a new method to estimate the SSB from the crossover differences using a three-dimensional nonparametric model based onU, SWH, and the Mean Wave Period (MWP). Evaluated by the separate annual data sets from 2009 to 2011, the SSB values estimated with the presented method can decrease the variance of the crossover Sea Surface Height (SSH) differences by 1.64 cm super(2), or 1.28 cm RMS, and decrease the variance of the Sea Level Anomalies (SLA) by 0.92 cm super(2), or 0.96 cm RMS in comparison to the SSB values in the Geophysical Data Records (GDR) of Jason-2. It is of great significance for improving the precision of altimeter products.